The inclusion of desirable characteristics to polymeric substrates has historically required a physical association of chemical materials to the substrate during the manufacturing process itself. For example, imparting color to a polymer is historically done by intermixing or compounding pigment or dye particles into a melted polymer either before polymerization or before forming into the final desired shape so that the dye particles can penetrate throughout the material and impart color to the final product.
Such methods have several drawbacks such as the dye particle is subjected to one or more melt/cool cycles during the manufacture of the final article which could result in degradation of the dye and alterations of color relative to that desired. A first heat step is present when the dye is incorporated into the melted polymeric material itself, and a second occurs when the article is formed into the final article shape such as by extrusion or other thermoforming.
Other prior methods of imparting desirable physical or chemical characteristics to polymeric substrates such as color or weathering rely on coating of the final article such as by painting color or other materials onto the surface of the article. Such configurations are subject to degradation such as by cracking, peeling, chipping or other that removes all or a portion of the coated material and reveals weaknesses on the overall article. Further, coatings must have sufficient flexibility to maintain integrity on a flexible substrate and such flexibility is difficult to achieve.
As such, there is a desire to develop new methods and systems for imparting desirable physical or chemical characteristics to polymeric substrates such as linear polymeric substrates.